Jaw for clip applier

ABSTRACT

Jaws of a surgical clip applier with housings formed thereon and methods for manufacturing and use during a procedure to apply surgical clips to a vessel, duct, shunt, etc. are provided. In one exemplary embodiment, a surgical clip applier is provided having jaws on a distal end thereof with a rigid internal frame and an outer housing formed around the internal frame. The jaws of the surgical clip applier can include a variety of features to facilitate placement of surgical clips, including features to align a clip with the jaws and to prevent clip fallout during formation.

FIELD

Clip appliers having an improved jaw structure, and methods for usingand manufacturing the same, are provided herein.

BACKGROUND

A variety of surgical procedures require application of clips to sealand/or secure tissue, requiring a surgical clip applier for ligating ablood vessel, a duct, shunt, a portion of body tissue, etc. duringsurgery. The jaws of most surgical clip appliers are formed through aprocess of metal stamping or machining, which can limit the possiblegeometry of the jaws. For example, rails of the jaws are designed tohold a clip in a clip track, however sufficient clearance is required inorder to accommodate varying clip heights or other deformities betweenclips. This clearance can result in surgical clips being free to shiftor wiggle in the clip tracks, which could result in clip malformation orclip fallout.

Accordingly, there remains a need for clip appliers having an improvedstructure for formation and placement of clips during surgicalprocedures.

SUMMARY

Clip appliers having improved jaws and methods for using andmanufacturing the same are provided herein. In one embodiment, asurgical clip applier is provided and includes an elongate shaft and ajaw assembly at a distal end of the elongate shaft. The jaw assembly caninclude a metal frame having a proximal portion coupled to the elongateshaft and a distal portion including first and second jaws movablebetween open and closed positions for engaging tissue therebetween. Thefirst and second jaws can each have an engagement feature formedthereon. The jaw assembly can also include a first outer housing aroundthe first jaw and a second outer housing around the second jaw. Theengagement feature can prevent movement of the first and second outerhousings relative to the metal frame. The first and second outerhousings can also have opposed inward facing surfaces, with each inwardfacing surface having a clip track formed therein and extendinglongitudinally therealong for receiving and guiding a clip into thejaws.

In one embodiment, the first and second outer housings can be overmoldedaround the first and second jaws, and in another embodiment, the firstand second outer housings can be configured to be coupled to the firstand second jaws through one of adhesive, welding, and mechanicalengagement means.

In some embodiments, the first and second jaws can include opposedinward facing surfaces, and the engagement feature can be a protrusionformed on the inward facing surface. The protrusion on each of the firstand second jaws can extend through the outer housing such that theprotrusion is configured to contact a clip seated in the clip track.

The jaw assembly can be formed from various materials. In oneembodiment, the first and second outer housings can be formed from apolymeric material. The metal frame can have a modulus of elasticitythat is greater than a modulus of elasticity of a material forming thefirst and second outer housings.

The housings can include various features. For example, the first andsecond outer housings can each include a plurality of fingers protrudinginto the clip track for retaining a clip therein. The plurality offingers can be flexible. The first and second outer housings can alsoeach include upper and lower rails that define the clip track. In oneembodiment, at least one cut-out can be formed in at least one of theupper and lower rails for allowing a user to view a clip seated in theclip track. In other embodiments, the first and second outer housingscan each have upper and lower protrusions positioned on opposed sides ofthe clip track for retaining a clip seated in the clip track.

In another embodiment, a jaw insert for use with a clip applier deviceis provided and includes a metal body having a proximal portion and adistal portion with first and second arms having opposed inward facingsurfaces. Each inward facing surface can have at least one protrusionformed thereon. The jaw insert can also include first and secondhousings on the first and second arms, respectively. The first andsecond housings can include opposed inward facing surfaces that eachdefine a clip track extending therealong for seating a clip therein. Theat least one protrusion on each of the first and second arms can extendthrough the inward facing surface of the first and second housings,respectively, such that the at least one protrusion on each of the firstand second arms is configured to contact a clip seated in the cliptrack.

In one embodiment, the first and second housings can be overmolded ontothe first and second arms, and in another embodiment, the first andsecond housings can be configured to be coupled to the first and secondarms through one of adhesive, welding, and mechanical engagement means.

The protrusion can be configured to prevent longitudinal sliding of thefirst and second housings. In certain embodiments, the protrusion can bepositioned at a substantial mid-portion of the clip track such that theprotrusion is configured to engage a bend zone on a clip seated in theclip track.

The jaws can be formed from various materials. For example, the metalbody can be made of a first material and the first and second housingscan be made of a second material. The first material can have a modulusof elasticity that is greater than a modulus of elasticity of the secondmaterial.

The housings can include various other features. For example, each ofthe first and second housings can have a plurality of fingers protrudinginto the clip track configured for retaining a clip therein. In oneaspect, the metal body can be made of a first material, the first andsecond housings can be made of a second material, and the plurality offingers can be made of a third material. The third material can have amodulus of elasticity that is less than a modulus of elasticity of thefirst material and a modulus of elasticity of the second material.

In other embodiments, the inward facing surface of the first and secondhousings can include upper and lower rails that define the clip track.At least one cut-out can be formed in at least one of the upper andlower rails for allowing a user to view a clip seated in the clip track.

In another embodiment, a method of manufacturing a jaw assembly of asurgical clip applier is provided and can include forming a metal framedefining first and second jaws configured to grasp tissue therebetween.Each jaw can have an engagement feature thereon. The method can alsoinclude molding first and second housings around the first and secondjaws, respectively, to form opposed inward facing surfaces having a cliptrack formed therein and extending therealong for receiving and guidinga clip into the jaws. The engagement feature can prevent slidingmovement of the first and second housings relative to the first andsecond jaws.

In one embodiment, the engagement feature can be a protrusion thatextends through the housing and that is configured to contact a clipseated in the clip track. Each housing can include upper and lower railsdefining the clip track. At least one of the upper and lower rails canhave at least one finger protruding into the clip track. The method canalso include injection molding a third material into cavities formed inthe clip track to form a plurality of fingers extending into the cliptrack.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a side view of one exemplary embodiment of a surgical clipapplier;

FIG. 2 is an exploded view of a distal portion of the surgical clipapplier of FIG. 1;

FIG. 3 is a perspective view of a distal portion of the surgical clipapplier of FIG. 1;

FIG. 4A is a perspective, partially transparent view of a proximalportion of the surgical clip applier of FIG. 1;

FIG. 4B is another perspective view of the proximal portion of thesurgical clip applier of FIG. 1;

FIG. 5 is a side, transparent view of an embodiment of a portion of ajaw assembly for use with a surgical clip applier;

FIG. 6 is a front, transparent view of an inward facing surface of oneof the jaws of the surgical clip applier in the direction AA of FIG. 5;

FIG. 7 is a side, transparent view of another embodiment of a portion ofa jaw assembly for use with a surgical clip applier;

FIG. 8 is a side, transparent view of another embodiment of a portion ofa jaw assembly for use with a surgical clip applier;

FIG. 9 is a side, transparent view of another embodiment of a portion ofa jaw assembly for use with a surgical clip applier;

FIG. 10 is a front, transparent view of an inward facing surface ofanother embodiment of a jaw;

FIG. 11 is a front, transparent view of an inward facing surface of yetanother embodiment of a jaw;

FIG. 12 is a cross-sectional view of another embodiment of a jaw;

FIG. 13 is a cross-sectional view of still another embodiment of a jaw;

FIG. 14 is a cross-sectional view of another embodiment of a jaw;

FIG. 15 is a cross-sectional view of yet another embodiment of a jaw;and

FIG. 16 is a cross-sectional view of still another embodiment of a jaw.

DETAILED DESCRIPTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those skilled in the art will understand that the devices andmethods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the present invention is defined solely by the claims. Thefeatures illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments. Suchmodifications and variations are intended to be included within thescope of the present invention.

A surgical clip applier can generally be used to apply surgical clips toa vessel, duct, shunt, etc., during a surgical procedure. An exemplarysurgical clip applier can include a jaw assembly having a frame with apair of jaws and a housing overmolded onto the jaws with various clipaligning and engaging features. For example, the overmolded housing canhave inward facing surfaces that define a clip track for receiving andguiding a clip into the jaws. The outer overmolded housing can allow fora variety of different structures and geometries to better controlformation and placement of surgical clips that are not possible withother surgical clip appliers, such as clip appliers having jaws formedthrough a stamping or machining process.

A surgical clip applier can generally have a variety of different formswith a variety of different jaws and clip tracks. FIGS. 1-4B illustrateone embodiment of a surgical clip applier 100. A person skilled in theart will appreciate that the jaw assemblies disclosed herein can be usedwith any clip applier device, or with any device having jaws. Theillustrated clip applier is merely one example of a device for use withthe jaw assemblies disclosed herein, and it is not intended to belimiting. As shown, the surgical clip applier 100 generally includes ahousing 102 having a stationary handle 104 and a movable handle ortrigger 106 that is pivotally coupled to the housing 102. An elongateshaft 108 extends distally from the housing 102 and includes a jawassembly 110 formed on a distal end 108 d thereof and including firstand second jaws 112, 114 that are movable between open and closedpositions. The first and second jaws 112, 114 include opposed inwardfacing surfaces and each inward facing surface has a clip track formedtherealong for receiving and guiding legs of a clip into the first andsecond jaws 112, 114. The elongate shaft 108 can be rotated with respectto the housing 102 via a rotation knob 103.

As shown in FIGS. 2 and 3, the elongate shaft 108 can include an outersupport tube 120, an upper shroud 122 coupled distally to the outer tube120, and a lower shroud 124. The outer support tube 120 and the upperand lower shrouds 122, 124 form an outer casing of the shaft 108. Asshown in FIGS. 2 and 3, a clip stack 126 including multiple surgicalclips is disposed within a clip track or holder 128 of the shaft 108proximal to the first and second jaws 112, 114, and is biased distally.A floor 130 extends beneath the clip stack 126 for maintaining the clipstack 126 in alignment within the shaft 108, and for guiding adistal-most clip 126 d into the jaws 112, 114. A lifter spring 132 ispositioned just proximal to the jaws 112, 114 and distal to the clipstack 126 for preventing distal movement of the clip stack 126, with thedistal-most clip 126 d disposed around the lifter spring 132. A feederbar 134 extends through the elongate shaft 108 for feeding thedistal-most clip 126 d into the jaws. As shown in FIG. 3 illustratingthe clip applier 100 with the upper and lower shrouds 122, 124 removed,a former tube 136 extends around a proximal end of the jaws 112, 114 andis movable distally to cam the jaws 112, 114 to a closed position forforming a clip 127 disposed therebetween.

The surgical clip applier 100 has a clip forming assembly includingvarious components that operate together to close the jaws 112, 114 whenthe trigger 106 is activated to thereby cause a clip (e.g., clip 127)disposed in the jaws to be applied (formed) to the tissue. The clipforming assembly encompasses the former tube 136 and other componentsthat are coupled to the trigger 106 configured to be activated to movethe former tube 136 distally to thereby close the jaws 112, 114. A clipadvancing assembly of the surgical clip applier 100 includes the feederbar 134 that is also coupled to the trigger 106, via a link 107extending proximally from the trigger 106, as shown in FIGS. 4A and 4B.In this way, when the trigger 106 is activated, the feeder bar 134 iscaused to move proximally, opposite to a distal direction in which theformer tube 136 is moved upon activation of the trigger 106.

The clip forming and clip advancing assemblies can have any suitableconfigurations. For example, in the illustrated embodiment, as shown inFIGS. 4A and 4B, the former tube 136 of the clip forming assembly iscoupled, via an inner coupling 138, to a former plate 140 in the handle102 that is, in turn, coupled to the trigger 106 via a pin 141, and thefeeder bar 134 of the clip advancing assembly is coupled to the trigger106 via a feeder plate 142 that is also coupled to the trigger 106, viathe link 107. As shown in FIG. 4A, the feeder plate 142 has arms 144 a,144 b at a distal end thereof that are disposed over and mate with aproximal end of an outer coupling 146 (shown partially transparent). Aconnecting pin 148 at a distal end of the outer coupling 146 attachesthe feeder bar 134 to the outer coupling 146. FIGS. 4A and 4B illustratethe handle 102 with part of an outer casing removed, and FIG. 4B showsthe handle 102 without the feeder plate 142, for illustration purposesonly. It should be appreciated that the surgical clip applier 100 caninclude various other components and assemblies that are not describedherein for the sake of simplicity.

In use, when the trigger 106 of the handle 102 is activated (e.g., movedtowards the stationary handle 104), the former plate 140 of the clipforming assembly is advanced distally to cause the former tube 136 toadvance distally over the jaws 112, 114, thereby camming the jaws 112,114 to the closed position. At the same time, the feeder plate 142 ofthe clip advancing assembly is moved proximally, thereby pulling thefeeder bar 134 proximally to position the feeder bar 134 proximal of thedistal-most clip 126 d of the clip stack 126. Once the clip 127,disposed in the jaws 112, 114 such that clip's legs are received withinthe clip track of each of the jaws, is fully formed, the trigger 106 isreleased, which causes the clip forming assembly to move proximallywhile the clip advancing assembly moves distally. FIG. 2 shows the clip127 in an original, pre-formed configuration. The proximal movement ofthe clip forming assembly causes the former tube 136 to retract relativeto the jaws, thus allowing the jaws 112, 114 to move to the originalopen position, thereby releasing the formed clip. The distal movement ofthe clip advancing assembly causes the feeder bar 134 to move distally,and the feeder bar 134 thereby pushes the distal-most clip 126 ddistally, overcoming the biasing force of the lifter spring 132 andcausing the lifter spring 132 to deflect out of the way, therebyallowing the distal-most clip 126 d to be advanced into the jaws 112,114. In this way, the distal-most clip becomes positioned in the jaws'clip track, like the clip 127 in FIG. 3. The floor 130 helps guide thedistal-most clip into the clip tracks of the jaws 112, 114.

A person skilled in the art will appreciate that, while a trigger isshown and described, the clip appliers disclosed herein need not includea trigger, and can have a variety of other actuation mechanisms. Forexample, the clip applier can be powered and can include an actuationbutton for actuating a motor to control firing of the device. In otherembodiments, the housing can be configured to couple to a robotic ortelemanipulator system, such that actuation of the device is controlledthrough the robotic system.

A variety of different jaw assemblies incorporating various overmoldedfeatures can be used with a clip applier, such as the clip applier 100illustrated in FIGS. 1-4A. The use of an overmolded housing can allowvarious features to be incorporated into the jaws that are not otherwiseachievable using a typical stamping process for forming metal jaws.

FIGS. 5 and 6 illustrate a portion of one embodiment of a jaw assembly500 that can be used with a clip applier, such as the clip applier 100,and that can be configured to grasp tissue and form and apply surgicalclips, similar to the first and second jaws 112, 114 discussed aboveregarding clip applier 100.

The illustrated jaw assembly 500 includes a frame having a proximalportion 500 p (only a portion of which is shown) that is configured toextend into the distal end of an elongate shaft of a clip applier, and adistal portion 500 d with first and second jaws 502, 504 forming anapproximate Y-shape. The first and second jaws 502, 504 can each includea tip portion 506, 508 having opposed inward facing surfaces 514, 515from which engagement features, such as protrusions 510, 511, can extendtowards one another into a central opening of the Y-shape of the jaws500. The protrusions 510, 511 can be configured to help retain theovermolded housing on each jaw 502, 504, as will be discussed in moredetail below. In certain embodiments, the protrusions 510, 511 can alsoprovide support to a clip seated within the jaws during clip formation,such as being configured to provide a rigid surface that can directlycontact and compress a clip. In certain exemplary embodiments, theprotrusions 510, 511 can be configured to contact a bend zone or curvein the clip configured to assist in clip formation and closure, as willalso be discussed in more detail below. A shroud 513 similar to theupper shroud 122 can be provided.

The engagement features, such as protrusions 510, 511, can have avariety of shapes and sizes, and can be positioned at various locations.In the illustrate embodiment, the protrusions 510, 511 are generallyrectangular in shape, and the protrusions 510, 511 extend across atleast part of a height of the surface 514 or entirely across the heightof the surface 541, and along a portion of the length of each tipportion 506, 508, in the proximal/distal direction. There can be one ormore protrusions on each tip portion 506, 508.

The jaw frame can be formed from various materials, but in an exemplaryembodiment the jaw frame is formed from a stamped, machined, ElectricalDischarge Machining (EDM), or Direct Metal Laser Sintering (DMLS) metal.The metal can vary in hardness (or a material's resistance toindentation as measured by the modulus of elasticity scale), dependingon desired properties of the material. The jaw frame should besufficiently flexible to allow the jaws to move between opened andclosed positions, while having sufficient stiffness to preventdeformation of the jaws when forces are applied thereto. Since the metalframe need not include clip tracks or other features for retaining aclip therein, the process for manufacturing the frame can besignificantly simplified.

As indicated above, features can be formed around the tip portion 506,508 of the first and second jaws 502, 504. For example, features can beovermolded onto the tip portion or can be molded separately and attachedto the tip portion by a variety of means, such as adhesives, laser weld,snap features, interference fit, etc. As illustrated in FIG. 5,overmolded housings 520, 522 can be formed over the tip portions 506,508. The overmolded housings 520, 522 can partially or fully surroundthe tip portions 506, 508, and can include opposed inward facingsurfaces 530, 531 positioning in alignment with the inward facingsurfaces 514, 515 of the tip portions 506, 508. Each inward facingsurface 530, 531 can have features that define, for example, a cliptrack 532, 533 extending longitudinally therealong for receiving andguiding legs of a clip 540 into the first and second jaws 502, 504. Incertain embodiments, the clip tracks 532, 533 can be in the form of agenerally rectangular-groove extending from a proximal end to a distalend of each inward facing surface 530, 531. Each clip track 532, 533 canbe defined by opposed upper and lower rails (only one rail 532 a, 533 aon each clip track 532, 533 is shown) extending longitudinally alongupper and lower edges of the inward facing surface 530, 531 of eachhousing 520, 522. The opposed legs of the clip 540 can thus extendbetween the rails such that the legs of the clip 540 are axially alignedwith one another.

As indicated above, the protrusions 510, 511 can help prevent slidingmovement of the overmolded housings 520, 522. For example, eachprotrusion 510, 511 can extend at least partially into the housing 520,522 to thereby retain the housing on the jaws. This can be achievedduring manufacturing by overmolding the housings 520, 522, e.g., usinginjection molding or other molding techniques, directly onto the tipportions 506, 508 such that the protrusions 510, 511 extend into thebody of the housings 520, 522, thereby preventing movement of thehousings 520, 522. The housings 520, 522 can be made with a variety ofmaterials, such as various plastics, liquid crystal polymer (LCP),elastomers, etc., and can vary in hardness (or a material's resistanceto indentation as measured by the modulus of elasticity scale),depending on desired properties of the material. In some embodiments,the modulus of elasticity of the overmolded housings 520, 522 can beless than a modulus of elasticity of at least the tip portions 506, 508of the first and second jaws 502, 504.

The protrusions 510, 511 can also assist in clip formation. Inparticular, the protrusions 510, 511 can be flush, can sit proud, or canbe slightly subflush of the outer surface of each clip track 532, 533such that the protrusions 510, 511 will contact a clip either directlyor indirectly (while still providing structural support and a rigidsurface) when the clip is seated in the clip tracks 532, 533. In anexemplary embodiment, the protrusions 510, 511 are flush with the outersurface so that the protrusions 510, 511 directly contact a clip seatingin the clip track. As a result, the protrusions 510, 511 can provide arigid surface for applying a force directly to the clips to aid in clipformation. In an exemplary embodiment, each protrusion 510, 511 ispositioned to engage a bend zone of the clip, e.g., a region where theclip bends to move from the open configuration to the closedconfiguration. This is illustrated in FIG. 8, which shows protrusions710, 711 located at about a mid-portion along the length of each tipportion and in contact with the bend zone. In other embodiments, thehousings 520, 522 can be molded separately and attached to the tipportions 506, 508 by a variety of means, such as adhesives, laserwelding, snap features, interference fit, etc.

In use, a clip advancing assembly can advance a clip 540 distally intothe jaws 502, 504 such that the legs of the clip 540 are received withinthe clip track 532, 533 of each of the jaws 502, 504. The first andsecond jaws 502, 504 can move to the closed position, grasping tissuetherebetween. This can be achieved using a former tube, for example,that is advanced around the jaws 502, 504, as previously discussedherein with respect to clip applier 100. When the jaws are closed, theclip 540 is compressed around tissue grasped therebetween. Theprotrusions 510, 511 act to provide additional structural force fordeforming the clip 540 around the tissue.

The overmolded housings can have a variety of features and structuresformed thereon as injection molding materials onto the jaws can allowfor a variety of geometries that are not possible when jaws are onlystamped or machined. FIG. 7 illustrates another embodiment of a jawassembly 600 with overmolded housings 620, 622, similar to jaw assembly500 with overmolded housings 520, 522. The illustrated jaw assembly 600has a frame with a proximal portion 600 p (only a portion of which isshown) that is configured to extend into the distal end of an elongateshaft of a clip applier, and a distal portion 600 d with first andsecond jaws 602, 604. The first and second jaws 602, 604 can eachinclude a tip portion 606, 608 having opposed inward facing surfaces614, 615 from which engagement features, such as protrusions 610, 611,can extend towards one another. Overmolded features can be formed overthe tip portions 606, 608, such as the overmolded housings 620, 622 withopposed inward facing surfaces 630, 631. Each inward facing surface 630,631 can have a clip track 632, 633 formed therealong for receiving andguiding legs of a clip 640. Each clip track 632, 633 can be defined byopposed upper and lower rails (only one rail 632 a, 633 a on each cliptrack 632, 633 is shown) extending longitudinally along upper and loweredges of the inward facing surface 630, 631 of each housing 620, 622.The opposed legs of the clip 640 can extend between the rails such thatthe legs of the clip 640 are axially aligned with one another. A shroud613 similar to the upper shroud 122 can be provided.

In this embodiment, the opposed inward facing surfaces 630, 631 can alsohave ridges or protrusions 638, 639 formed on the upper and/or lowerrails 632 a, 633 a that extend towards the opposed inward facing surface630, 631 and surround the clip tracks 632, 633. As illustrated in FIG.7, the protrusions 638, 639 can be configured to increase a depth of theclip tracks 632, 633 and/or to increase clip visibility while a clip iswithin the clip tracks 632, 633. The protrusions 638, 630 can alsoassist in grasping tissue to be clamped. The protrusions 638, 639 can beidentical on each opposed jaw or can be complementary to one another formating with one another when the jaws are closed. The protrusions 638,639 can be made of the same material as the overmolded housings 620, 622or can be made of a different material with a different modulus ofelasticity, for example the protrusions 638, 639 can have a modulus ofelasticity less than a modulus of elasticity of the material of theovermolded housings 620, 622, and thus less than a modulus of elasticityof the metal frame. When the protrusions 638, 639 are made of adifferent material, the overmolded housings 620, 622 can have cavitiesformed therein for receiving material for the protrusions 638, 639during manufacturing.

While FIG. 7 illustrates a plurality of ridges or protrusions 638, 639formed on the upper and lower rails that define the clip track, theovermolded housings 720, 722 can have a number of different protrusionsor other features formed thereon. FIG. 8 illustrates another embodimentof a jaw assembly 700 with overmolded housings 720, 722, similar to jawassembly 500 with overmolded housings 520, 522. The illustrated jawassembly 700 can have a frame with a proximal portion 700 p (only aportion of which is shown) that is configured to extend into the distalend of an elongate shaft of a clip applier, and a distal portion 700 dwith first and second jaws 702, 704. The first and second jaws 702, 704can each include a tip portion 706, 708 having opposed inward facingsurfaces 714, 715 from which engagement features, such as protrusions710, 711, can extend towards one another. Overmolded features can beformed over the tip portions 706, 708, such as overmolded housings 720,722 with opposed inward facing surfaces 730, 731. Each inward facingsurface 730, 731 can have a clip track 732, 733 formed therealong forreceiving and guiding legs of a clip 740. Each clip track 732, 733 canbe defined by opposed upper and lower rails (only one rail 732 a, 733 aon each clip track 732, 733 is shown) extending longitudinally alongupper and lower edges of the inward facing surface 730, 731 of eachhousing 720, 722. The opposed legs of the clip 740 can extend betweenthe rails such that the legs of the clip are axially aligned with oneanother. A shroud 713 similar to the upper shroud 122 can be provided.

The opposed inward facing surfaces 730 can have protrusions 738, 739formed thereon that extend towards the opposed inward facing surface730, 731, similar to the protrusions 638, 639. However, in thisembodiment the protrusions 738, 739 can extend from the upper and/orlower rails 632 a, 633 a around the protrusions 710, 711, and can beconfigured to increase retention of the clip 740 within the jaw assembly700 and help prevent clip fallout during formation. In other words,upper and lower protrusions on the upper and lower rails of each cliptrack can define a gap therebetween that is less than a height of theclip track, such that the upper and lower protrusions will help engage aclip seated therebetween. The protrusions 738, 739 can be made of thesame material as the overmolded housings 720, 722 or can be made of adifferent material with a different modulus of elasticity, for examplehaving a modulus of elasticity less than the material of the overmoldedhousings 720, 722. When the protrusions 738, 739 are made of a differentmaterial, the overmolded housings 720, 722 can have cavities formedtherein for receiving material for the protrusions 738, 739 duringmanufacturing.

In other embodiments, various windows or openings can be formed inovermolded housings along clip tracks to allow users to view a locationof a clip therein. As discussed above, the protrusions 638 can beconfigured to increase clip visibility while a clip is within the cliptrack 632, but openings can be formed anywhere along a length of theclip track. FIG. 9 illustrates a jaw assembly 800 with overmoldedhousings 820, 822, similar to jaw assembly 500 with overmolded housings520, 522. The illustrated jaw assembly 800 has a frame with a proximalportion 800 p (only a portion of which is shown) that is configured toextend into the distal end of an elongate shaft of a clip applier, and adistal portion 800 d with first and second jaws 802, 804. The first andsecond jaws 802, 804 can each include a tip portion 806, 808 havingopposed inward facing surfaces 814, 815 from which engagement features,such as protrusions 810, 811, can extend towards one another. Overmoldedfeatures can be formed over the tip portions 806, 808, such as theovermolded housings 820, 822 with opposed inward facing surfaces 830,831. Each inward facing surface 830, 831 can have a clip track 832, 833formed therealong for receiving and guiding legs of a clip 840. Eachclip track 832, 833 can be defined by opposed upper and lower rails(only one rail 832 a, 833 a on each clip track 832, 833 is shown)extending longitudinally along upper and lower edges of the inwardfacing surface 830, 831 of each housing 820, 822. The opposed legs ofthe clip 840 can extend between the rails such that the legs of the clipare axially aligned with one another. A shroud 813 similar to the uppershroud 122 can be provided.

In this embodiment, the overmolded housings 820, 822 can have openingsformed therein, for example openings formed in proximal and/or distalportions of the upper and/or lower rails. FIG. 9 illustrates openingsformed in distal ends of the upper and lower rails 832 a, 833 a, howeverthe openings can be formed at any location that allows for visibility ofa clip seating in the clip tracks. In the illustrated embodiment, ends842, 843 of the clip 840 can be seen by a user through the distal windowto thereby increase visibility of the clip 840 and assist with alignmentduring placement.

The clip track can also have a variety of configurations because of theinjection molding process that are not possible with jaws that arestamped or machined. FIG. 10 illustrates another embodiment of a jawassembly 900 with overmolded housings (with only one jaw and overmoldedhousing 920 being illustrated), similar to jaw assembly 500 withovermolded housings 520, 522. While only shown in part, the illustratedjaw assembly 900 has a frame with a proximal portion that is configuredto extend into the distal end of an elongate shaft of a clip applier,and a distal portion 900 d with first and second jaws (with only thefirst jaw 902 being illustrated, and the second jaw being a mirror imageof the first jaw 902). The first and second jaws 902 can each include atip portion 906 having opposed inward facing surfaces 914 from whichengagement features, such as protrusions (not illustrated), can extendtowards one another. Overmolded features can be formed over the tipportions 906, such as the overmolded housings 920 with opposed inwardfacing surfaces 930. Each inward facing surface 930 can have a cliptrack 932 formed therealong for receiving and guiding legs of a clip940. Each clip track 932 can be defined by opposed upper and lower railsextending longitudinally along upper and lower edges of the inwardfacing surface 930 of each of the first and second housings 920. Theopposed legs of the clip 940 can extend between the rails such that thelegs of the clip are axially aligned with one another.

In this embodiment, the clip track 932 is tapered distally with a widerportion of the clip track 932 on a proximal end 932 p thereof closer toa clip applier and a narrower portion of the clip track 932 on a distalend 932 d thereof. The taper in the clip track 932 can be configured toallow easy and effective feeding of the clip 940 into the clip track 932while also reducing clearance between the clip 940 and the clip track932 as the clip 940 is fully fed into the clip track 932 and approachesthe distal end 932 d thereof. Widths of distal and proximal ends of thetapered clip track 932 can vary, for example a width of the clip track932 at the proximal end 932 p can be approximately double a width of theclip track 932 at the distal end 932 d.

Protrusions can also extend into the clip track itself. FIG. 11illustrates another embodiment of a jaw assembly 1000 with overmoldedhousings (with only one jaw and overmolded housing 1020 beingillustrated), similar to jaw assembly 500 with overmolded housings 520,522. The illustrated jaw assembly 1000 can have a frame with a proximalportion that is configured to extend into the distal end of an elongateshaft of a clip applier, and a distal portion 1000 d with first andsecond jaws (with only the first jaw 1002 being illustrated, and thesecond jaw being a mirror image of the first jaw 1002). The first andsecond jaws 1002 can each include a tip portion 1006 having opposedinward facing surfaces 1014 from which engagement features, such asprotrusions (not illustrated), can extend towards one another.Overmolded features can be formed over the tip portions 1006, such asthe overmolded housings 1020 with opposed inward facing surfaces 1030.Each inward facing surface 1030 can have a clip track 1032 formedtherealong for receiving and guiding legs of a clip 1040. Each cliptrack 1032 can be defined by opposed upper and lower rails extendinglongitudinally along upper and lower edges of the inward facing surface1030 of each of the first and second housings 1020. The opposed legs ofthe clip 1040 can extend between the rails such that the legs of theclip are axially aligned with one another.

As shown, protrusions 1038 can be formed at various locations along theclip track 1032, for example being formed on and extending from each ofthe rails, and configured to extend into the clip track 1032 and engagethe clip 1040 therein. The protrusions 1038 can be configured to assistin holding and aligning the clip 1040 in the clip track 1032 duringformation. The protrusions 1038 can take a variety of forms, such asflexible fingers, pegs, fins, pads, wedges, etc., and there can be oneor more protrusions 1038 formed in the clip track 1032. Widths, lengths,and stiffness levels (modulus of elasticity) of the protrusions 1038 canvary depending on desired uses. For example, the protrusions 1038 canhave lengths such that a clip entering the clip track 1032 will beengaged by protrusions 1038 on either side of the clip track 1032 and beforced into an aligned, middle position in the clip track 1032, and theprotrusions 1038 can be configured to flex or bend out of the way of aclip as it advances along the clip track 1038. This can be beneficialwith surgical clips that have widths that vary along a length of theclip itself. The protrusions 1038 can be made of the same material asthe overmolded housing 1020 or can be made of a different material witha different modulus of elasticity, for example having a modulus ofelasticity less than a modulus of elasticity of the material of theovermolded housing 1020 to allow the protrusions 1038 to bend and flexwith the clip 1040 while the housing 1020 provides stiffer support. Whenthe protrusions 1038 are made of a different material, the overmoldedhousing 1020 can have cavities formed therein for receiving material forthe protrusions 1038 during manufacturing.

Additional features can be added to a clip applier to improve clipretention in a jaw using an overmolded process, for example to keep aclip securely in a clip track with high clip retention forces whilestill having strong clip forming abilities. FIG. 12 illustrates anotherembodiment of a jaw assembly 1100 with overmolded housings (with only across-section of one jaw 1102 and overmolded features 1120 beingillustrated), similar to jaw assembly 500 with overmolded housings 520,522. The jaw 1102 of the illustrated jaw assembly 1100 is rigid and hasovermolded features 1120 in the form of polymer rails formed thereon. Asa clip 1140 is inserted into the jaw 1102, the polymer rails of theovermolded features 1120 can be configured to deform only slightly andallow for the clip 1140 to snap into place, being configured to keep theclip 1140 retained more securely against the jaw 1102 than many commondesigns that use only metal jaws. As illustrated in FIG. 12, the clip1140 is configured to sit securely in a clip track 1132 of the jaw 1102.

Another embodiment with a similar structure is illustrated in FIG. 13. Ajaw assembly 1200 with overmolded housings (with only a cross-section ofone jaw 1202 and overmolded features 1220 being illustrated), similar tojaw assembly 500 with overmolded housings 520, 522. The jaw 1202 of theillustrated jaw assembly 1200 is rigid and has overmolded features 1220in the form of elastomer rails formed thereon. As a clip 1240 isinserted into the jaw 1202, the elastomer rails of the overmoldedfeatures 1220 can be configured to deform and allow for the clip 1240 todeform the overmolded features 1220 and secure itself into place. Asillustrated in FIG. 13, the clip 1240 is configured to sit securely in aclip track 1232 of the jaw 1202. The elastomer rails of the overmoldedfeatures 1220 can have a lower modulus of elasticity than a modulus ofelasticity of the polymer rails of the overmolded features 1120. Theovermolded features 1120 can thus cause the clip 1140 to snap into placein the jaw 1102 while the overmolded features 1220 allow for moredeformation of the elastomer rails and an easier release of the clip1240.

FIG. 14 illustrates another embodiment of a jaw assembly 1300 withovermolded housings (with only a cross-section of one jaw 1302 andovermolded features 1320, 1322 being illustrated), similar to jawassembly 500 with overmolded housings 520, 522. The jaw 1302 of theillustrated jaw assembly 1300 is rigid and has first overmolded features1320 in the form of polymer sidewall rails formed on either side of thejaw 1302 and second overmolded features 1322 in the form of elastomerinserts formed in a clip track 1332. As a clip 1340 is inserted into thejaw 1302, the polymer sidewall rails of the overmolded features 1320 canbe configured to guide the clip 1340 along the clip track 1332,providing a rigid guide. The elastomer inserts can be positioned in theclip track 1332 itself and provide an interference fit between the clip1340 and the clip track 1332 so that the clip 1340 can sit securely inthe clip track 1323 while benefiting from a rigid guide from theovermolded features 1320 because the polymer sidewalls of the overmoldedfeatures 1320 can have a higher modulus of elasticity than a modulus ofelasticity of the elastomer inserts of the overmolded features 1322.

While various structures are provided above for overmolded features,additional features and structures are possible. For example, FIG. 15illustrates another embodiment of a jaw assembly 1400 with overmoldedhousings (with only a cross-section of one jaw 1402 and overmoldedfeatures 1420 being illustrated), similar to jaw assembly 500 withovermolded housings 520, 522. The jaw 1402 of the illustrated jawassembly 1400 is rigid and has overmolded features 1420 in the form ofpolymer sidewall rails formed on either side of the jaw 1402 with arms1422 formed to extend slightly into a clip track 1432 and help secure aclip 1440 therein.

Another possible geometry is illustrated in FIG. 16, in which anotherembodiment of a jaw assembly 1500 with overmolded housings (with only across-section of one jaw 1502 and overmolded features 1520 beingillustrated), similar to jaw assembly 500 with overmolded housings 520,522. The jaw 1502 of the illustrated jaw assembly 1500 is rigid and hasovermolded features 1520 in the form of polymer sidewall rails formed oneither side of the jaw 1502 in a dovetail shape such that inner surfaces1522 of the sidewall rails are thicker than outer surfaces and are thusconfigured to extend slightly into a clip track 1532 to help secure aclip 1540 therein. While the materials discussed herein are polymers andelastomers, any materials can be used that can have lower values formodulus of elasticity than the rigid jaws.

The various clip retaining features disclosed herein can have a varietyof other configurations, as disclosed in U.S. application Ser. No.[______] (Atty. Docket No. 47364-309F01US, END8262USNP), filed on evendate herewith and entitled “Clip Retention for Surgical Clip Applier,”which is hereby incorporated by reference in its entirety.

During manufacturing, a rigid frame defining one of the jaws 500, 600,700, 800, 900, 1000 discussed above can be stamped from a rigidmaterial, such as metal, including the one or more protrusions extendingfrom distal portions thereof. Housings defining the overmolded housings520, 522, 620, 622, 720, 722, 820, 822, 920, 1020 can be formed byinjection molding a material, such as various plastics, liquid crystalpolymer (LCP), elastomer, etc., around each of the corresponding jaws500, 600, 700, 800, 900, 1000 to form the housings with the opposedinward facing surfaces defining the clip tracks therein. The protrusionson the metal frame can prevent sliding movement of the overmoldedhousings relative to the frame.

The various protrusions or other features of the overmolded housings620, 622, 720, 722, 820, 822, 920, 1020 discussed above located aroundand/or within the clip tracks can either be formed of the same materialas the overmolded housings 620, 622, 720, 722, 820, 822, 920, 1020 andcan be injection molded simultaneously with the overmolded housings 620,622, 720, 722, 820, 822, 920, 1020 or can be made from a differentmaterial, such as various plastics, liquid crystal polymer (LCP),elastomer, etc., and can be formed after injection molding of theovermolded housings 620, 622, 720, 722, 820, 822, 920, 1020 has beencompleted. In such an embodiment, material for the various protrusionsof the overmolded housings 620, 622, 720, 722, 820, 822, 920, 1020 canbe injection molded into cavities or spacings formed on the overmoldedhousings 620, 622, 720, 722, 820, 822, 920, 1020 and configured toreceive material for the protrusions therein. In some embodiments,material used to injection mold the overmolded housings 620, 622, 720,722, 820, 822, 920, 1020 can be varied within a single overmoldedhousing to create varying material properties within one overmoldedhousing, for example increasing friction in various molded parts of themolded housings 620, 622, 720, 722, 820, 822, 920, 1020. Injectionmolding can thus occur in one step or over multiple steps depending on adesired complexity of the overmolded housings and how many materials areto be used in the overmolded housings.

In the present disclosure, like-numbered components of the embodimentsgenerally have similar features, and thus within a particular embodimenteach feature of each like-numbered component is not necessarily fullyelaborated upon. Sizes and shapes of the devices described herein, andthe components thereof, can depend at least on the anatomy of thesubject in which the devices will be used, the size and shape ofcomponents with which the devices will be used, and the methods andprocedures in which the devices will be used. The figures providedherein are not necessarily to scale. Although the devices and methodsdisclosed herein are generally directed to surgical techniques, they canalso be used in applications outside of the surgical field.

Although the invention has been described by reference to specificembodiments, it should be understood that numerous changes may be madewithin the spirit and scope of the inventive concepts described.Accordingly, it is intended that the invention not be limited to thedescribed embodiments, but that it have the full scope defined by thelanguage of the following claims.

What is claimed is:
 1. A surgical clip applier, comprising: an elongateshaft; a jaw assembly coupled to a distal end of the elongate shaft, thejaw assembly including a metal frame having a proximal portion coupledto the elongate shaft and a distal portion including first and secondjaws movable between open and closed positions for engaging tissuetherebetween, the first and second jaws each having an engagementfeature formed thereon, and a first outer housing around the first jawand a second outer housing around the second jaw, the engagement featurepreventing movement of the first and second outer housings relative tothe metal frame, and the first and second outer housings having opposedinward facing surfaces, each inward facing surface having a clip trackformed therein and extending longitudinally therealong for receiving andguiding a clip into the jaws.
 2. The surgical clip applier of claim 1,wherein the first and second outer housings are overmolded around thefirst and second jaws.
 3. The surgical clip applier of claim 1, whereinthe first and second outer housings are configured to be coupled to thefirst and second jaws through one of adhesive, welding, and mechanicalengagement means.
 4. The surgical clip applier of claim 1, wherein thefirst and second jaws include opposed inward facing surfaces, andwherein the engagement feature comprises a protrusion formed on theinward facing surface.
 5. The surgical clip applier of claim 4, whereinthe protrusion on each of the first and second jaws extends through theouter housing such that the protrusion is configured to contact a clipseated in the clip track.
 6. The surgical clip applier of claim 1,wherein the first and second outer housings are formed from a polymericmaterial.
 7. The surgical clip applier of claim 1, wherein the metalframe has a modulus of elasticity that is greater than a modulus ofelasticity of a material forming the first and second outer housings. 8.The surgical clip applier of claim 1, wherein the first and second outerhousings each include a plurality of fingers protruding into the cliptrack for retaining a clip therein.
 9. The surgical clip applier ofclaim 1, wherein the first and second outer housings each include upperand lower rails that define the clip track.
 10. The surgical clipapplier of claim 9, wherein at least one cut-out is formed in at leastone of the upper and lower rails for allowing a user to view a clipseated in the clip track.
 11. The surgical clip applier of claim 9,wherein the first and second outer housings each have upper and lowerprotrusions positioned on opposed sides of the clip track for retaininga clip seated in the clip track.
 12. A jaw insert for use with a clipapplier device, comprising: a metal body having a proximal portion and adistal portion with first and second arms having opposed inward facingsurfaces, each inward facing surface having at least one protrusionformed thereon; and first and second housings on the first and secondarms, respectively, the first and second housings including opposedinward facing surfaces that each define a clip track extendingtherealong for seating a clip therein, and the at least one protrusionon each of the first and second arms extending through the inward facingsurface of the first and second housings, respectively, such that the atleast one protrusion on each of the first and second arms is configuredto contact a clip seated in the clip track.
 13. The jaw insert of claim12, wherein the first and second housings are overmolded onto the firstand second arms.
 14. The jaw insert of claim 12, wherein the first andsecond housings are configured to be coupled to the first and secondarms through one of adhesive, welding, and mechanical engagement means.15. The jaw insert of claim 12, wherein the protrusion is configured toprevent longitudinal sliding of the first and second housings.
 16. Thejaw insert of claim 12, wherein the protrusion is positioned at asubstantial mid-portion of the clip track such that the protrusion isconfigured to engage a bend zone on a clip seated in the clip track. 17.The jaw insert of claim 12, wherein the metal body is made of a firstmaterial and the first and second housings are made of a secondmaterial, the first material having a modulus of elasticity that isgreater than a modulus of elasticity of the second material.
 18. The jawinsert of claim 12, wherein each of the first and second housings has aplurality of fingers protruding into the clip track configured forretaining a clip therein.
 19. The jaw insert of claim 18, wherein themetal body is made of a first material, the first and second housingsare made of a second material, and the plurality of fingers are made ofa third material, the third material having a modulus of elasticity thatis less than a modulus of elasticity of the first material and a modulusof elasticity of the second material.
 20. The jaw insert of claim 12,wherein the inward facing surface of the first and second housingsincludes upper and lower rails that define the clip track.
 21. A methodof manufacturing a jaw assembly of a surgical clip applier, comprising:forming a metal frame defining first and second jaws configured to grasptissue therebetween, each jaw having an engagement feature thereon; andmolding first and second housings around the first and second jaws,respectively, to form opposed inward facing surfaces having a clip trackformed therein and extending therealong for receiving and guiding a clipinto the jaws, the engagement feature preventing sliding movement of thefirst and second housings relative to the first and second jaws.
 22. Themethod of claim 21, wherein the engagement feature comprises aprotrusion that extends through the housing and is configured to contacta clip seated in the clip track.
 23. The method of claim 21, whereineach housing includes upper and lower rails defining the clip track, atleast one of the upper and lower rails having at least one fingerprotruding into the clip track.
 24. The method of claim 21, furthercomprising injection molding a third material into cavities formed inthe clip track to form a plurality of fingers extending into the cliptrack.